Substrate processing apparatus and substrate processing method

ABSTRACT

A substrate processing apparatus removes foreign substances from a substrate at high removal efficiency. The substrate processing apparatus includes: a scrubber to perform surface processing of the substrate by bringing a scrubbing member into sliding contact with a first surface of the substrate, a hydrostatic support mechanism for supporting a second surface of the substrate via fluid pressure without contacting the substrate, the second surface being an opposite surface of the first surface, a cleaner to clean the processed substrate, and a dryer to dry the cleaned substrate. The scrubber brings the scrubbing member into sliding contact with the first surface while rotating the scrubbing member about a central axis of the scrubber.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of U.S. application Ser. No. 13/772,031filed Feb. 20, 2013 which claims priority to Japanese Patent ApplicationNo. 2012-35365, filed on Feb. 21, 2012, the entire contents of which arehereby incorporated by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to an apparatus and a method forprocessing a front-side surface and/or a backside surface of asubstrate, such as a wafer, which requires high cleanliness.

Description of the Related Art

In recent years, various devices including memory circuits, logiccircuits, and image sensors (e.g., complimentarymetal-oxide-semiconductor (CMOS) sensors) have become more and morehighly integrated. In the processes of fabricating these devices,foreign substances, such as fine particles and dusts, may be attached tothe devices. The foreign substances attached to the devices could be acause of a short circuit between interconnects and a malfunction of thecircuit. Therefore, in order to increase reliability of the devices, itis necessary to clean a wafer on which the devices are fabricated so asto remove the foreign substances from the wafer.

The foreign substances, such as fine particles and dusts, may also beattached to a backside surface of the wafer, i.e., a bare siliconsurface. The foreign substances on the backside surface of the wafer maycause the wafer to be separated from a stage reference surface of anexposure apparatus and/or may cause the wafer surface to tilt withrespect to the stage reference surface, resulting in a patterning shiftor a focal length error. In order to prevent such problems, it isnecessary to remove the foreign substances from the backside surface ofthe wafer as well.

There has recently been developed a patterning apparatus based onnanoimprint technology, rather than the optical exposure technology. Inthis nanoimprint technology, a mold, which has predefined interconnectpatterns, is pressed against a resin material formed on a wafer totransfer the interconnect patterns to the resin material. In suchnanoimprint technology, it is required to remove the foreign substancesexisting on the surface of the wafer in order to avoid transfer ofunwanted spots between the mold and the wafer and also between wafers.

It has been customary to scrub the wafer with a pen-shaped brush or aroll sponge while rotating the wafer. However, such a cleaning techniquehas a low capability of removing the foreign substances. In particular,it is difficult for the conventional cleaning technique to remove theforeign substances having a size of 100 nm or more.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above. It istherefore an object of the present invention to provide a substrateprocessing apparatus and a substrate processing method which are capableof removing foreign substances from a front-side surface and/or abackside surface of a substrate, such as a wafer, at high removalefficiency. More particularly, it is an object of the present inventionto provide a substrate processing apparatus and a substrate processingmethod which are capable of cleaning and drying the substrate afterremoving the foreign substances from the substrate.

One aspect of the present invention for achieving the above objectprovides a substrate processing apparatus, including: a scrubberconfigured to perform surface processing of a substrate by bringing ascrubbing member into sliding contact with a first surface of thesubstrate; a hydrostatic support mechanism having a substrate supportsurface for supporting a second surface of the substrate via fluidpressure without contacting the substrate, the second surface being anopposite surface of the first surface; a cleaner configured to clean thesubstrate processed by the scrubber; and a dryer configured to dry thesubstrate cleaned by the cleaner. The scrubber is configured to bringthe scrubbing member into sliding contact with the first surface of thesubstrate while rotating the scrubbing member about a central axis ofthe scrubber.

Another aspect of the present invention provides a substrate processingmethod, including: performing surface processing of a substrate bybringing a scrubbing member into sliding contact with a first surface ofthe substrate while supporting a second surface of the substrate byfluid pressure in a non-contact manner, the second surface being anopposite surface of the first surface; cleaning the substrate that hasbeen subjected to the surface processing; and drying the cleanedsubstrate.

According to embodiments of the present invention, the second surface ofthe substrate (e.g., a front-side surface of the substrate) is supportedby the hydrostatic support mechanism. Therefore, the scrubber can applya relatively high load to the first surface of the substrate (e.g., abackside surface of the substrate). Under such a high load, thescrubbing member of the scrubber is placed in sliding contact with thefirst surface to thereby slightly scrape off the first surface.Consequently, the scrubber can remove the foreign substances firmlyattached to the first surface. In particular, the scrubber can removethe foreign substances having a size of 100 nm or more with greatlyimproved efficiency. Moreover, since the second surface of the substrateis supported by the hydrostatic support mechanism which does not contactthe substrate, the scrubber can remove the foreign substances from thefirst surface without causing damage to devices formed on the secondsurface.

Furthermore, according to embodiments of the present invention, thesubstrate processing apparatus can remove the foreign substances fromthe substrate, clean the substrate, and dry the substrate. Therefore, itis not necessary to transport the substrate to other sites for theseprocesses. That is, the substrate can be scrubbed, cleaned, and driedsuccessively in one processing chamber, so that debris and mists (e.g.,processing liquid and cleaning liquid) are prevented from spreading out.As a consequence, the substrate processing apparatus can be installed ina clean environment, such as a clean room.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A, 1B, and 1C are schematic views each showing a substrateprocessing apparatus according to an embodiment of the presentinvention;

FIG. 2 is a flowchart showing a sequence of performing surfaceprocessing of a substrate using a hydrostatic support mechanism;

FIGS. 3A and 3B are schematic views each showing a more specific exampleof the substrate processing apparatus including the hydrostatic supportmechanism;

FIG. 4 is a side view of the substrate processing apparatus according toan embodiment of the present invention;

FIG. 5 is a cross-sectional view showing detailed structure of asubstrate rotating mechanism;

FIG. 6 is a plan view of a spin cover and a plurality of chucks;

FIG. 7 is a cross-sectional view of the substrate rotating mechanismwith a wafer in an elevated position;

FIG. 8 is a view showing internal structures of a scrubber and a swingarm;

FIG. 9 is a bottom view of the scrubber;

FIG. 10 is a cross-sectional view of a tape cartridge;

FIG. 11 is a view showing another example of the scrubber;

FIG. 12 is a view showing the manner in which cleaning tapes are woundwhen the scrubber is in a retreat position;

FIG. 13 is a perspective view of another example of the tape cartridge;

FIG. 14 is a side view of the tape cartridge shown in FIG. 13;

FIG. 15 is a front view of the tape cartridge shown in FIG. 13;

FIG. 16 is a plan view of the tape cartridge shown in FIG. 13;

FIG. 17 is a cross-sectional view taken along line D-D in FIG. 15;

FIG. 18 is a cross-sectional view taken along line E-E in FIG. 15;

FIG. 19 is a cross-sectional view taken along line F-F in FIG. 15;

FIG. 20 is a cross-sectional view taken along line G-G in FIG. 15;

FIG. 21 is a cross-sectional view of the hydrostatic support mechanism;

FIG. 22 is a plan view of a support stage of the hydrostatic supportmechanism;

FIG. 23 is a plan view illustrating motions of a two-fluid jet nozzle;

FIG. 24 is a view showing an example of the substrate processingapparatus including a drying liquid supply nozzle;

FIG. 25 is a view showing an example of the substrate processingapparatus including a drying gas supply nozzle;

FIG. 26A is a plan view showing a clamp of a chuck;

FIG. 26B is a side view of the clamp;

FIG. 27A is a plan view of the clamp when holding a wafer;

FIG. 27B is a plan view of the clamp when releasing the wafer;

FIG. 28A is a cross-sectional view taken along line A-A in FIG. 6;

FIG. 28B is a cross-sectional view taken along line B-B in FIG. 28A;

FIG. 29 is a schematic view illustrating arrangement of a second magnetand a third magnet, as viewed from an axial direction of the chuck;

FIG. 30A is a cross-sectional view taken along the line A-A in FIG. 6when the chuck is elevated by a lift mechanism;

FIG. 30B is a cross-sectional view taken along line C-C in FIG. 30A;

FIG. 31 is a cross-sectional view showing another example of thesubstrate rotating mechanism;

FIG. 32 is a cross-sectional view showing still another example of thesubstrate rotating mechanism;

FIG. 33 is a side view showing another example of the scrubber;

FIG. 34 is a plan view of the scrubber and the wafer;

FIG. 35 is a plan view of a substrate processing system including aplurality of substrate processing apparatuses according to theembodiment of the present invention;

FIG. 36 is a plan view showing another example of the substrateprocessing system;

FIG. 37 is a side view of the substrate processing apparatuses arrangedin upper and lower tiers;

FIG. 38 is a side view illustrating wafer processing lines; and

FIG. 39 is a side view illustrating wafer processing lines.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of a substrate processing apparatus according to the presentinvention will be described below with reference to the drawings.Identical or corresponding parts are denoted by identical referencenumerals in FIGS. 1 to 39, and will not be described in duplication.

FIGS. 1A through 1C are schematic views each showing a substrateprocessing apparatus according to embodiments of the present invention.As shown in FIGS. 1A through 1C, a load of a processing head (not shown)is applied to a one-side surface (e.g., an upper surface) of a substrateW, and a hydrostatic support mechanism 90 is arranged so as to face theopposite surface (e.g., a lower surface) of the substrate W. Thehydrostatic support mechanism 90 includes a support stage 91 having afluid supply passage 92 defined therein for introducing a pressure fluid1, such as a liquid or a gas.

In the example shown in FIG. 1A, the fluid supply passage 92 is coupledto a pocket (recess) 91 b, formed on the support stage 91, for retainingthe pressure fluid 1 therein. The load on the substrate W is received bythe pressure fluid in the pocket 91 b and is further received by thepressure fluid that overflows the pocket 91 b onto a support surface 91a of the support stage 91.

In the example shown in FIG. 1B, the support stage 91 does not have theabove-described pocket 91 b. In this example, the pressure fluid 1,which has been introduced through the fluid supply passage 92, spreadsover the support surface 91 a in its entirety to support the loadapplied to the substrate W. In the example shown in FIG. 1C, the supportsurface 91 a of the support stage 91 has a plurality of through-holes 91c defined therein. The pressure fluid 1 is supplied from the fluidsupply passage 92 onto the support surface 91 a in its entirety throughthe through-holes 91 c. The hydrostatic support mechanism 90 having suchstructures can support the load on the substrate W through the pressurefluid 1. Even if the substrate W has on its lower surface micro LSIstructures which are in the fabrication process, substrate processingcan be performed with no damage to the LSI structures, because only thepressure fluid contacts the lower surface of the substrate W and nosubstrate holding structure directly contacts the substrate W. Examplesof the pressure fluid 1 introduced through the fluid supply passage 92include a liquid, such as water or oil, and a gas, such as high-pressureair. In the case where the substrate processing apparatus is used in theLSI fabrication process, ultrapure water or clean high-pressure air maybe used as the pressure fluid 1 from the viewpoint of preventingcontamination of the substrate W.

Surface processing of the substrate using the above-discussedhydrostatic support mechanism 90 will be described below with referenceto a flowchart shown in FIG. 2. First, the substrate, to be processed,is transported to the support stage 91 by a transfer robot. If thesubstrate has on its one-side surface micro LSI structures which are inthe process of their fabrication, it may be that the transfer robot doesnot touch that surface of the substrate. For example, the transfer robotholds a peripheral edge of the substrate with its hand or holds asubstrate surface having no micro device structures thereon with a handhaving a vacuum chuck or the like. Subsequently, the hand of thetransfer robot releases the substrate on the support stage 91, so thatthe substrate surface, which is opposite to the surface to be processed,is supported by the hydrostatic support mechanism 90. The substrateprocessing apparatus may have an auxiliary holding mechanism for holdingthe substrate after the substrate is placed on the support stage 91until the pressure fluid is introduced into the support stage 91. Forexample, a chuck configured to hold the peripheral edge of the substratemay be used as such an auxiliary holding mechanism.

Subsequently, surface processing is performed so as to remove foreignsubstances and scratches from the surface of the substrate.Specifically, the processing head is brought into sliding contact withthe surface to be processed, and applies a load to the surface. Theprocessing head has a substrate contact surface which may be made of asoft material, such as sponge, nonwoven fabric, foamed polyurethane, orany of these materials containing abrasive grains, or a polishing tape.The soft material to be used may be softer than a material forming thesurface, to be processed, of the substrate. The material of the surfaceof the substrate may be silicon, silicon compound, gallium, galliumcompound, metal, metal compound, or organic compound. The abrasivegrains may be made of any one of silicon dioxide, silicon carbide,silicon nitride, aluminum oxide, and diamond, or may be made of amixture of selected ones from these materials.

When the processing head is in sliding contact with the surface of thesubstrate to perform the above-described surface processing (i.e.,removal process), a processing liquid, such as a polishing liquid orpure water, may be supplied onto the surface to be processed. Theprocessing liquid supplied can expel from the substrate the debris(e.g., the foreign substances and film fragments removed) and reactionproducts produced when the surface is processed. The processing liquidmay contain a component capable of dissolving a film forming the surfaceto be processed, abrasive grains for removing the film and the reactionproducts, and/or a component for preventing reattachment of the foreignsubstances and the reaction products once removed. The processing liquidmay be neutral or alkaline or acid. The processing head may be of anysize. A desired number of processing heads may be used. In order toenable the hydrostatic support mechanism 90 to reliably support thesubstrate, the processing head may have substantially the same size as aregion where the hydrostatic support mechanism 90 can retain the fluidpressure. During surface processing of the substrate, the substrate maybe rotated about its central axis.

After the surface processing, the substrate is cleaned so that thedebris, such as the foreign substances and the reaction productsremoved, is fully expelled from the substrate. Although cleaning of thesubstrate may be performed using a different stage in the substrateprocessing apparatus, cleaning of the substrate may be performed usingthe same support stage 91 in order to prevent the debris from spreadingaround. When substrate cleaning is performed using the support stage 91,the hydrostatic support mechanism 90 is used to support the substratesurface opposite to the processed surface by the fluid pressure with nocontact with the substrate in the same manner as the surface processing.The processing head is not used in this cleaning process. Instead, acleaning liquid is supplied onto the processed surface. At the sametime, additional cleaning techniques, such as two-fluid jet cleaning ormegasonic cleaning, may be performed so as to clean the processedsurface more efficiently than the case where only the cleaning liquid isused to rinse the processed surface. The cleaning technique to be usedmay be a non-contact type cleaning technique, such as the two-fluid jetcleaning, rather than a contact type cleaning technique which cleans thesubstrate with a cleaning tool, such as a brush or a sponge, for rubbingthe processed surface. This is because the cleaning tool used in thecontact type cleaning technique contacts the substrate directly and isthus likely to cause back contamination from the cleaning tool. Thecleaning liquid may be pure water. In order to prevent the reattachmentof the debris (e.g., the foreign substances and the reaction productsremoved), a surface active agent may be added to the cleaning liquid. Itis also possible to use the cleaning liquid having a controlled pH forbetter cleaning performance.

After the substrate cleaning process, the substrate is dried. In orderto prevent the debris and the mist (e.g., the cleaning liquid and thepolishing liquid) from spreading out, the substrate may be dried withouttransporting the substrate to other stage. Various drying processes maybe employed for drying the substrate. For example, the substrate may berotated at a high speed to remove the cleaning liquid via centrifugalforce, a clean gas may be supplied to the cleaned surface of thesubstrate to expel the cleaning liquid or droplets thereof off thesubstrate, or a low-vapor-pressure solvent may be supplied to thecleaned surface of the substrate so that the cleaning liquid is replacedwith the low-vapor-pressure solvent, which is then evaporated todryness. Finally, the dried substrate is unloaded from the substrateprocessing apparatus by the transfer robot using the hand as describedabove.

(1) EXAMPLE 1

More specific examples of the substrate processing apparatus includingthe hydrostatic support mechanism 90 will be described below withreference to FIGS. 3A and 3B. FIG. 3A is a conceptual view of thesubstrate processing apparatus including the hydrostatic supportmechanism 90 disposed below the substrate W. The hydrostatic supportmechanism 90 has the fluid supply passage 92 for the pressure fluid 1.The pressure fluid 1 is supplied to the fluid supply passage 92 througha supply pipe (not shown). Before processing of the substrate W isstarted, the support stage 91 of the hydrostatic support mechanism 90 iselevated toward the substrate W. After the substrate W is processed, thesupport stage 91 is lowered. Alternatively, the substrate processingapparatus may have a mechanism for elevating and lowering the substrateW. In FIG. 3A, the hydrostatic support mechanism 90 has the structureshown in FIG. 1A. The hydrostatic support mechanism 90 may have thestructure shown in FIG. 1B or the structure shown in FIG. 1C, or anotherstructure.

The processing head 50 is disposed so as to face the substrate surfaceat the opposite side of the hydrostatic support mechanism 90. Theprocessing head 50 has a scrubbing member 61 made of a soft material,such as sponge, nonwoven fabric, foamed polyurethane, or the like. Thescrubbing member 61 may be a polishing tape configured to process thesurface of the substrate W. The processing head 50 further includes aholder 59 which holds the scrubbing member 61. This holder 59 may beomitted. The processing head 50 is supported by a support element (notshown) which is configured to enable the processing head 50 to rotateabout its central axis, rotate about another axis, oscillate, and/ormove in the vertical direction. The processing head 50 can bring thescrubbing member 61 into contact with the substrate W under a load thatis transmitted to the processing head 50 through the support element.The scrubbing member 61 performs surface processing by slightly scrapingoff the surface of the substrate W to remove the foreign substances fromthe surface of the substrate W and/or by removing at least a portion ofthe material that forms the surface of the substrate W. This surfaceprocessing of the substrate using the scrubbing member 61 will behereinafter referred to as “scrubbing process”.

When the scrubbing process is performed on the surface of the substrateW, the processing liquid is supplied onto the surface of the substrate Wthrough a processing liquid supply pipe 4. The processing liquid may bepolishing liquid or pure water, as described above with reference toFIG. 2. Further, in order to clean the substrate W, the cleaning liquidis supplied to the substrate W through the cleaning liquid supply pipe5. A two-fluid jet nozzle or a megasonic cleaning nozzle may be disposedon a tip end of the cleaning liquid supply pipe 5 or separately from thecleaning liquid supply pipe 5. The cleaning liquid supplied from thecleaning liquid supply pipe 5 may be pure water or a liquid containingsurface active agent. It is also possible to use the cleaning liquidhaving a controlled pH. The cleaning liquid supply pipe 5 may supplyonly one type of cleaning liquid or may supply two or more types ofcleaning liquids successively or simultaneously. The processing liquidsupply pipe 4 and the cleaning liquid supply pipe 5 may be the samecommon pipe.

The substrate processing apparatus includes a plurality of chucks 11 forholding the peripheral edge of the substrate W and rotating thesubstrate W at a high speed so as to dry the substrate. The substrateprocessing apparatus may include a solvent supply pipe and/or a gassupply pipe (not shown) for supplying a low-vapor-pressure solventand/or a gas to the substrate W. In the substrate processing apparatusshown in FIG. 3A, the scrubbing process, the cleaning process, and thedrying process are performed using the same stage, while these processesmay be performed using different stages. A robot may be provided fortransferring the substrate between the stage or stages and a substrateloading and unloading section.

The substrate processing apparatus has a housing (a partition) 6 and anexhauster 8. The housing 6 defines a processing chamber 7 therein. Anupper portion of the housing 6 has a plurality of clean air inlets 6 a,and a lower portion of the housing 6 has exhaust ducts 9. The exhauster8, which is mounted to the upper portion of the housing 6, sends cleanair through the clean air inlets 6 a into the processing chamber 7,forcing a gas in the processing chamber 7 out of it through the exhaustducts 9. The above-described scrubbing process, the cleaning process,and the drying process are performed in this processing chamber 7, sothat various by-products (e.g., the debris and the cleaning mist)generated in these processes are prevented from spreading out of thesubstrate processing apparatus. Since the substrate is cleaned and driedin the same processing chamber 7 in which the scrubbing process isperformed, the substrate having its dried surface in a clean state canbe removed from the substrate processing apparatus. A conventionalsubstrate processing apparatus cannot clean and dry the processedsubstrate in the same chamber. For this reason the conventionalapparatus cannot be installed in a clean environment, such as a cleanroom. In contrast, the substrate processing apparatus according toembodiments of the present invention does not permit the debris and thelike to spread out of the substrate processing apparatus. Accordingly,the substrate processing apparatus can be installed in the clean roomand hence can be used as an LSI circuit fabrication apparatus.

(2) EXAMPLE 2

FIG. 3B is a conceptual view of the substrate processing apparatusincluding the hydrostatic support mechanism 90 disposed above thesubstrate W. The substrate processing apparatus shown in FIG. 3B hasbasic structures identical to those of the substrate processingapparatus shown in FIG. 3A.

(3) EXAMPLE 3

A method of performing surface processing of the substrate using thesubstrate processing apparatus according to an embodiment of the presentinvention will be described below. A substrate (e.g., a substrate in theprocess of LSI fabrication) is placed in the substrate processingapparatus with its one-side surface (e.g., a device surface) facing thehydrostatic support mechanism 90 and the opposite surface (e.g., thebackside surface) facing the processing head 50. The peripheral edge ofthe substrate is held by the chucks 11. The substrate is then rotatedwhile its device surface is supported by the hydrostatic supportmechanism 90. In this state, the processing head 50 presses the backsidesurface, on which no device is formed, of the substrate to removescratches and particles from the backside surface. The substrate may notbe held by the chucks 11 throughout the surface processing.

When scrubbing of the substrate is performed, the backside surface ofthe substrate is supplied with the cleaning liquid which may be purewater, an aqueous solution containing surface active agents, or alkalineor acid cleaning liquid. The cleaning liquid may be supplied to thebackside surface of the substrate when the processing head 50 is not incontact with the substrate. Since the hydrostatic support mechanism 90faces the device surface of the substrate, a gas may be used rather thana liquid as the pressure fluid supplied from the hydrostatic supportmechanism 90. This is because the liquid may cause corrosion of finepatterns which are in the process of device fabrication. In addition,when the device surface that has contacted the liquid is dried, defectssuch as watermarks or deformation of the fine patterns, may occur.

After the scrubbing process is terminated, the debris is removed off thesubstrate by the non-contact cleaning process, such as the two-fluid jetcleaning process. The two-fluid jet nozzle (not shown) used in thetwo-fluid jet cleaning process moves between the center and theperipheral portion of the rotating substrate while supplying a jet offluid to the substrate surface in its entirety to clean the substrate.In this two-fluid jet cleaning process, a jet of fluid mixture of aliquid (e.g., pure water) and a high-pressure gas is supplied to thesubstrate. Water with a carbon dioxide gas dissolved therein or othercleaning liquid may be used instead of the pure water. The high-pressuregas may be a clean gas containing as few fine particles as possible. Anykind of gas, such as atmospheric air or nitrogen, can be used so long asthere is no safety problem. A flow rate of the liquid used in thetwo-fluid jet cleaning process may be in a range of several mL/min toseveral hundreds mL/min, and a flow rate of the gas may be in a range ofseveral tens L/min to several hundreds L/min. After the cleaningprocess, the chucks 11, which are holding the peripheral edge of thesubstrate, rotate the substrate at a high speed to thereby dry thesubstrate. Instead of the spin drying process or in addition to the spindrying process, the low-vapor-pressure solvent, such as isopropylalcohol, may be supplied to the cleaned surface of the substrate so thatthe cleaning liquid on the substrate is replaced with thelow-vapor-pressure solvent, which is then evaporated to dryness.

The substrate to be processed may be a device wafer, a glass substrate,or the like. According to the present invention, the substrate can beprocessed without being bent, because the substrate is supported by thefluid pressure. Therefore, substrates having various sizes can beprocessed. For example, wafers having diameters of 100 mm, 150 mm, 200mm, 300 mm, and 450 mm can be processed according to the presentinvention. Glass substrates having large sizes can also be processed.

More specific examples of the substrate processing apparatus accordingto an embodiment of the present invention will be described below. FIG.4 is a side view of the substrate processing apparatus according to anembodiment of the present invention. As shown in FIG. 4, the substrateprocessing apparatus includes: a hollow substrate rotating mechanism 10for holding the wafer W as a substrate horizontally and rotating thewafer W about its central axis; a scrubber 50 as the processing head forscrubbing the upper surface of the wafer W, held by the substraterotating mechanism 10, to remove the foreign substances and thescratches from the upper surface of the wafer W; and the hydrostaticsupport mechanism 90 for supporting the lower surface of the wafer W viathe fluid pressure without contacting the substrate (i.e., in anon-contact manner).

The scrubber 50 is disposed above the wafer W held by the substraterotating mechanism 10, and the hydrostatic support mechanism 90 isdisposed below the wafer W held by the substrate rotating mechanism 10.The hydrostatic support mechanism 90 is disposed in an interior space ofthe substrate rotating mechanism 10. The substrate rotating mechanism10, the scrubber 50, and the hydrostatic support mechanism 90 areenclosed by the housing 6 that forms a partition. The housing 6 definesthe processing chamber 7 therein. The upper portion of the housing 6 hasthe multiple clean air inlets 6 a defined therein, and the lower portionof the housing 6 has the exhaust ducts 9 defined therein. The exhauster8, which is mounted to the upper portion of the housing 6, has: a fan8A; and a filter 8B for removing particles and dust from the airdelivered from the fan 8A. The exhauster 8 sends clean air through theclean air inlets 6 a into the processing chamber 7, forcing a gas in theprocessing chamber 7 out of it through the exhaust ducts 9. The surfaceprocessing (the scrubbing process), the cleaning process, and the dryingprocess, which will be described later in detail, are performedsuccessively in the processing chamber 7.

The substrate rotating mechanism 10 includes: the plurality of chucks 11for holding the peripheral edge of the wafer W and a hollow motor 12 forrotating the wafer W through the chucks 11. The substrate rotatingmechanism 10 has a cylindrical shape as a whole having the largeinterior space defined centrally. If the substrate rotating mechanism 10does not have such a large space underneath the wafer W, negativepressure may be produced below the wafer W when the wafer W is rotatedat a high speed. Such negative pressure is likely to attract dusts andparticles suspended in the air, which may be attached to the lowersurface of the wafer W. In this embodiment, since the hollow motor 12 isused, the substrate rotating mechanism 10 can be of the cylindricalshape forming the large interior space below the wafer W and cantherefore prevent such a problem. In addition, the hydrostatic supportmechanism 90 can be disposed in the interior space of the substraterotating mechanism 10.

FIG. 5 is a cross-sectional view showing a detailed structure of thesubstrate rotating mechanism 10. As shown in FIG. 5, the hollow motor 12has: a cylindrical rotor 12A and a stator 12B disposed so as to surroundthe rotor 12A. The rotor 12A has an inner circumferential surface havinga diameter larger than that of the wafer W. Use of such hollow motor 12Aallows the substrate rotating mechanism 10 to have the cylindrical shapewith the large interior space at the center thereof. The rotor 12Aincludes a plurality of permanent magnets 12 a embedded therein. Thehollow motor 12 is a sensorless IPM (Interior Permanent Magnet) motorwith no optical position sensor. The hollow motor 12 of this type can bemanufactured at low costs. Moreover, even if a liquid enters the hollowmotor 12, malfunction due to failure of the position sensor is notlikely to occur.

The stator 12B is fixed to a cylindrical stationary member 14. Acylindrical rotary base 16 is disposed radially inward of the stationarymember 14. The rotary base 16 is rotatably supported by a combination ofangular contact ball bearings 20 disposed between the stationary member14 and the rotary base 16. These two angular contact ball bearings 20are capable of bearing both a radial load and an axial load. Other typesof bearings may be used so long as they can support both a radial loadand an axial load. The stator 12B of the hollow motor 12 is secured tothe stationary member 14. The rotor 12A of the hollow motor 12 issecured to the rotary base 16, so that the rotor 12A and the rotary base16 can rotate in unison with each other.

The chucks 11 are mounted to an upper portion of the rotary base 16 suchthat the chucks 11 are vertically movable. More specifically, the upperportion of the rotary base 16 has an annular flange 16 a projectingradially inward. The annular flange 16 a has a plurality of verticalthrough-holes in which the chucks 11 are inserted, respectively. Springs18 are disposed around lower portions of the chucks 11 respectively.These springs 18 have upper ends pushing the lower surface of the flange16 a upwardly and lower ends contacting spring stoppers 11 a, which aremounted to respective lower ends of the chucks 11. The chucks 11 areforced downward by the respective springs 18. The chucks 11 arerotatable in unison with the rotary base 16 by the hollow motor 12.

An annular spin cover (or spin cup) 25 is disposed radially outwardly ofthe chucks 11 so as to surround the wafer W held by the chucks 11. Thespin cover 25 is secured to an upper surface of the rotary base 16, sothat the spin cover 25 can rotate in unison with the wafer W. FIG. 6 isa plan view of the spin cover 25 and the chucks 11. As shown in FIG. 6,the spin cover 25 is shaped so as to surround the circumference of thewafer W in its entirety. The spin cover 25 has an upper end whose insidediameter is slightly larger than the diameter of the wafer W. The upperend of the spin cover 25 has a plurality of cutout portions 25 a atpositions corresponding to those of the chucks 11. Each cutout portion25 a is shaped so as to extend along the circumferential surface of eachchuck 11.

As shown in FIG. 5, the spin cover 25 has an inner circumferentialsurface having a vertical cross-sectional shape inclined radially inwardand defined by a smooth curved line. The upper end of the spin cover 25is located close to the wafer W. The spin cover 25 has oblique liquiddrain holes 25 b defined in a lower portion thereof

As shown in FIG. 4, a cleaning liquid supply nozzle 27 for supplyingpure water as the cleaning liquid onto the upper surface of the wafer Wis disposed above the wafer W. The cleaning liquid supply nozzle 27 iscoupled to a cleaning liquid source (not shown), so that the pure wateris supplied onto the upper surface of the wafer W through the cleaningliquid supply nozzle 27. When the wafer W is rotated about its own axisby the substrate rotating mechanism 10, the pure water, supplied to thewafer W, is expelled off the wafer W under centrifugal force. Further,the pure water is trapped by the inner circumferential surface of thespin cover 25 and flows into the liquid drain holes 25 b.

A lift mechanism 30 for elevating the chucks 11 is disposed below thechucks 11. The lift mechanism 30 includes: a ring stage 31 disposedbelow the chucks 11; a plurality of rods 32 supporting the ring stage31; and an air cylinder 33 as an actuator for elevating the rods 32. Thelift mechanism 30, which is separated from the rotary base 16, is notrotatable. As shown in FIG. 7, the air cylinder 33 is configured toelevate the ring stage 31 through the rods 32. The upward movement ofthe ring stage 31 moves the chucks 11 upwardly simultaneously. When theoperation of the air cylinder 33 is stopped, the chucks 11 are loweredby the springs 18 mounted to the chucks 11. FIG. 5 shows a state inwhich the chucks 11 are in a lowered position. The lift mechanism 30 andthe springs 18 constitute a vertically moving mechanism for verticallymoving the chucks 11.

Although not shown, instead of the air cylinders 33, a plurality ofelectric cylinders capable of elevating the respective chucks 11simultaneously may be provided. For example, four electric cylinders areprovided for the four chucks 11, respectively. In the case of using theelectric cylinders, the ring stage 31 is not provided. When the rotationof the wafer W stops, the chucks 11 are controlled so as to stop atpositions above the respective electric cylinders. Operations of theelectric cylinders are controlled by a common driver so that theelectric cylinders operate in synchronism.

Clamps 40 for holding the peripheral edge of the wafer W are mountedrespectively to the upper ends of the chucks 11. When the chucks 11 arein the lowered position shown in FIG. 5, the clamps 40 are in contactwith the peripheral edge of the wafer W to thereby hold the peripheraledge. When the chucks 11 are in the elevated position shown in FIG. 7,the clamps 40 are separated from the peripheral edge of the wafer W torelease the peripheral edge.

As shown in FIG. 4, the scrubber 50 is disposed at the upper side of thewafer W. The scrubber 50 is coupled to one end of a swing arm 53 througha scrubber shaft 51. The other end of the swing arm 53 is fixed to apivot shaft 54, which is coupled to a shaft rotating mechanism 55. Thisshaft rotating mechanism 55 is configured to rotate the pivot shaft 54such that the scrubber 50 moves between a processing position shown inFIG. 4 and a retreat position located radially outwardly of the wafer W.The pivot shaft 54 is further coupled to a scrubber elevating mechanism56 which moves the scrubber 50 vertically. This scrubber elevatingmechanism 56 is configured to elevate and lower the scrubber 50 throughthe pivot shaft 54 and the scrubber shaft 51. The scrubber 50 is loweredto contact the upper surface of the wafer W by the scrubber elevatingmechanism 56. The scrubber elevating mechanism 56 may include an aircylinder or a combination of a servomotor and a ball screw.

FIG. 8 is a view showing internal structures of the scrubber 50 and theswing arm 53. As shown in FIG. 8, a scrubber rotating mechanism 58 isprovided in the swing arm 53. This scrubber rotating mechanism 58 isconfigured to rotate the scrubber 50 about its central axis. Morespecifically, the scrubber rotating mechanism 58 includes: a pulley p1fixed coaxially to the scrubber shaft 51; a motor M1 mounted to theswing arm 53; a pulley p2 fixed coaxially to a rotational shaft of themotor M1; and a belt b1 riding on the pulleys p1 and p2. Rotation of themotor M1 is transmitted through the pulleys p1 and p2 and the belt b1 tothe scrubber shaft 51, which rotates the scrubber 50.

FIG. 9 is a bottom view of the scrubber 50. The scrubber 50 has a lowersurface that provides a circular scrubbing surface for scrubbing theupper surface of the wafer W (the front-side surface or the backsidesurface of the wafer W) that is held by the substrate rotating mechanism10. The scrubber 50 has a plurality of (three in FIG. 9) cleaning tapes61 as scrubbing members arranged so as to face the upper surface of thewafer W. The scrubber 50 has a plurality of (three in FIG. 9) tapecartridges 60 accommodating the cleaning tapes 61 therein, respectively.The tape cartridges 60 are removably installed in the scrubber 50.

When scrubbing the wafer W, the scrubber 50 is rotated about its centralaxis by the scrubber rotating mechanism 58 to rotate the cleaning tapes61 about the central axis of the scrubber 50, so that the cleaning tapes61 are placed in sliding contact with the upper surface of the wafer W.The scrubbing surface of the scrubber 50 is formed by the rotatingcleaning tapes 61. Since the lower surface of the wafer W is supportedby the fluid pressure, the scrubber 50 can press the cleaning tapes 61against the upper surface of the wafer W with a large load withoutbending the wafer W. Material forming the upper surface of the wafer Wis scraped off slightly by the sliding contact with the cleaning tapes61. Therefore, the foreign substances attached to the wafer W and thesurface scratches of the wafer W can be removed. An amount (or athickness) of the material scraped off the wafer W by the scrubber 50may be 50 nm or less. The surface of the wafer W that has been scrubbedmay have a surface roughness of 5 μm or less. In this manner, byslightly scrapping away the surface of the wafer W, the foreignsubstances stuck firmly into the wafer W and having a diameter of 100 nmor greater can be completely removed from the wafer W.

FIG. 10 is a cross-sectional view of the tape cartridge 60. As shown inFIG. 10, the tape cartridge 60 includes: the cleaning tape 61; a pressmember 62 for pressing the cleaning tape 61 against the wafer W; abiasing device 63 for biasing the press member 62 toward the wafer W; atape feeding reel 64 for feeding the cleaning tape 61; and a tapewinding reel 65 for winding the cleaning tape 61 that has been used inthe scrubbing process. The cleaning tape 61 advances from the tapefeeding reel 64 to the tape winding reel 65 via the press member 62. Thepress members 62 of the respective tape cartridges 60 extend in theradial direction of the scrubber 50 and are arranged at equal intervalsin a circumferential direction of the scrubber 50. Therefore, thecleaning tapes 61 have respective wafer contact surfaces (i.e.,substrate contact surfaces) extending in the radial direction of thescrubber 50. In FIG. 10, a spring is used as the biasing device 63.

The tape winding reels 65 of the tape cartridges 60 are coupled to oneends of tape winding shafts 67 as shown in FIGS. 8 and 9. Bevel gears 69are secured to the other ends of the tape winding shafts 67,respectively. These bevel gears 69, which are coupled to the tapecartridges 60, are in mesh with a bevel gear 70 which is coupled to arotational shaft of a motor M2 arranged in the scrubber 50. With theseconfigurations, the tape winding reels 65 are driven by the motor M2 towind the cleaning tapes 61. The motor M2, the bevel gears 69 and 70, andthe tape winding shafts 67 jointly construct a tape advancing mechanismfor advancing the cleaning tapes 61 from the tape feeding reels 64 tothe tape winding reels 65.

Each cleaning tape 61 has a width ranging from 10 mm to 60 mm and alength ranging from 20 m to 100 m. The cleaning tape 61 may be made ofnonwoven fabric, woven fabric, or knitted fabric. Nonwoven fabric harderthan PVA sponge may be used as the cleaning tape 61. The cleaning tape61 made of such nonwoven fabric can remove the foreign substances on thewafer W, particularly the foreign substances stuck into the surface ofthe wafer W. Instead of the cleaning tape 61, a polishing tape having onits one-side surface a polishing layer containing abrasive grains may beused as the scrubbing member.

When the wafer W is scrubbed, the cleaning tape 61 is advanced at apredetermined speed from the tape feeding reel 64 to the tape windingreel 65. Therefore, a new (i.e., unused) surface of the cleaning tape 61is brought into contact with the wafer W at all times. Each cleaningtape 61 has an end mark (not shown) near the terminal end thereof. Thisend mark is detected by an end-mark detection sensor 71 which isdisposed in proximity to the cleaning tape 61. When the end-markdetection sensor 71 detects the end mark on the cleaning tape 61, theend-mark detection sensor 71 sends a detection signal to an operationcontroller (not shown). Upon receiving the detection signal, theoperation controller produces a signal, such as a warning signal, forprompting a user to replace the cleaning tape 61 with new one. Since thetape cartridges 60 are removable, they can easily be replaced with newtape cartridges 60.

The retreat position of the scrubber 50 is located radially outwardly ofthe wafer W and the scrubber 50 is configured to be movable between theretreat position and the processing position. A bath (not shown)retaining pure water therein is provided in the retreat position. Whenthe scrubber 50 is in the retreat position, the lower surface (i.e., thescrubbing surface) of the scrubber 50 is immersed into the pure water inthe bath in order to prevent the cleaning tapes 61 from being dried. Thepure water in the bath is replaced with fresh pure water each time thescrubber 50 performs surface processing of the wafer W, so that the bathcontains clean pure water at all times.

FIG. 11 is a view showing another example of the scrubber 50. Thescrubber 50 shown in FIG. 11 does not include the motor M2 therein foradvancing the cleaning tapes 61. Instead, as shown in FIG. 12, the motorM2 and the bevel gear 70 are provided in the retreat position. When thescrubber 50 is lowered in the retreat position, the bevel gears 69 arebrought into mesh with the bevel gear 70. In this state, the motor M2 isactuated to advance the cleaning tapes 61 by a predetermined distancefrom the tape feeding reels 64 to the tape winding reels 65. Accordingto this example shown in FIG. 11, the structure of the scrubber 50 canbe simple, and consumption of the cleaning tapes 61 can be reducedbecause the cleaning tapes 61 are advanced intermittently.

FIGS. 13 through 20 show another example of the tape cartridge 60. Inthis example also, the scrubber 50 does not include the motor M2 thereinfor advancing the cleaning tapes 61. The tape feeding reel 64 and thetape winding reel 65 are mounted respectively to reel shafts 75A and75B, which are rotatably supported by respective bearings 76A and 76Bsecured to a reel housing 77. This reel housing 77 is secured to a ballspline nut 78. The reel housing 77 and the ball spline nut 78 arevertically movable relative to a spline shaft 79.

Brake wheels 80A and 80B are fixed to the reel shafts 75A and 75B,respectively. The tape feeding reel 64 and the brake wheels 80A arerotatable in unison with each other, and the tape winding reel 65 andthe brake wheels 80B are rotatable in unison with each other. The ballspline nut 78 is forced downward by a spring 82, so that the brakewheels 80A and 80B are pressed against a brake pad 81 by the spring 82.When the brake pad 81 is in contact with the brake wheels 80A and 80B,the brake wheels 80A and 80B and the tape feeding reel 64 and the tapewinding reel 65 coupled thereto are unable to rotate freely. Downwardlyextending pins 83 are fixed to the reel housing 77. These pins 83 arebrought into contact with pin stoppers (not shown) which are provided inthe retreat position of the scrubber 50.

A tape feeding gear 84A is mounted to the reel shaft 75A, and a tapewinding gear 84B is mounted to the reel shaft 75B, as shown in FIG. 19.The tape feeding gear 84A has a larger diameter than that of the tapewinding gear 84B. The tape feeding gear 84A and the tape winding gear84B are attached respectively to the reel shafts 74A and 75B throughone-way clutches 85A and 85B. The tape feeding reel 64, the tape windingreel 65, the brake wheels 80A and 80B, the tape feeding gear 84A, andthe tape winding gear 84B are vertically movable in unison relative tothe spline shaft 79. Rack gears 86A and 86B are disposed between thetape feeding gear 84A and the tape winding gear 84B. The tape feedinggear 84A is in mesh with the rack gear 86A, while the tape winding gear84B is in mesh the rack gear 86B. The press member 62, the brake pad 81,and the rack gears 86A and 86B are secured to an installation base 87.

When the scrubber 50 is lowered in the retreat position, the pins 83 arebrought into contact with the pin stoppers. At this time, the downwardmovements of the tape feeding reel 64, the tape winding reel 65, thebrake wheels 80A and 80B, the tape feeding gear 84A, and the tapewinding gear 84B, all of which are coupled to the pins 83, are stopped,while the press member 62, the brake pad 81, and the rack gears 86A and86B continue to move downwardly. As a result, the spring 82 iscompressed, and the brake pad 81 is separated from the brake wheels 80Aand 80B, allowing the tape feeding reel 64 and the tape winding reel 65to rotate freely. As the rack gears 86A and 86B are lowered, the tapefeeding gear 84A and the tape winding gear 84B, which are in engagementwith the rack gears 86A and 86B, rotate. The tape feeding reel 64rotates together with the tape feeding gear 84A to thereby unreel orfeed a new portion of the cleaning tape 61 by a predetermined length. Onthe contrary, the tape winding reel 65 does not rotate because of theone-way clutch 85B.

As the scrubber 50 is elevated, the spring 82 extends, and the rackgears 86A and 86B move upwardly to rotate the tape feeding gear 84A andthe tape winding gear 84B. The tape winding reel 65 rotates togetherwith the tape winding gear 84B to wind the used cleaning tape 61, whilethe tape feeding reel 64 does not rotate because of the one-way clutch85A. Since the tape winding gear 84B has a smaller diameter than that ofthe tape feeding gear 84A, the tape winding reel 65 makes morerevolutions than the tape feeding reel 64 does. As shown in FIG. 20, atoque limiter 88 is incorporated in the tape winding reel 65. This toquelimiter 88 is configured to permit the tape winding gear 84B to slipafter the tape winding reel 65 has wound the cleaning tape 61 to therebyapply a tension to the cleaning tape 61. When the brake pad 81 contactsthe brake wheels 80A and 80B, the tape winding reel 65 stops rotating,whereby the renewal of the cleaning tape 61 is terminated.

Since the tape cartridge 60 shown in FIGS. 13 through 20 requires nomotor for advancing the cleaning tape 61, the structure of the scrubber50 can be made simple. Furthermore, because the cleaning tape 61 isadvanced intermittently, the consumption of the cleaning tape 61 can bereduced. As can be seen from in FIGS. 15 and 16, the tape cartridge 60in this example has a symmetric structure, and each tape cartridge 60has two cleaning tapes 61.

FIG. 21 is a cross-sectional view of the hydrostatic support mechanism90. As shown in FIG. 21, the hydrostatic support mechanism 90 includes:the support stage 91 having the circular substrate support surface 91 awith a plurality of recesses 91 b as fluid reservoirs defined thereon; aplurality of fluid supply passages 92 coupled to the respective recesses91 b; and a support shaft 93 supporting the support stage 91. The fluidsupply passages 92 extend through the support shaft 93 and are coupledto a fluid source 96 through a rotary joint 95.

FIG. 22 is a plan view of the support stage 91. As shown in FIG. 22, therecesses 91 b are arranged at equal intervals along a circumferentialdirection of the support stage 91. The support stage 91 is disposedbelow the wafer W held by the substrate rotating mechanism 10 so thatthe recesses 91 b face the lower surface of the wafer W. The supportshaft 93 is vertically movably supported by a linear-motion guide (ballspline) 97. The support shaft 93 has its lower portion coupled to astage elevating device 98. This stage elevating device 98 is configuredto elevate the support stage 91 until the substrate support surface(i.e., the upper surface) 91 a reaches a position in proximity to thelower surface of the wafer W.

The hydrostatic support mechanism 90 further includes a stage rotatingmechanism 99. This stage rotating mechanism 99 has: a pulley p3 mountedto an outer circumferential surface of the linear-motion guide 97, amotor M3, a pulley p4 fixed coaxially to a rotational shaft of the motorM3, and a belt b2 riding on the pulleys p3 and p4. This stage rotatingmechanism 99 is configured to rotate the support stage 91 about thesupport shaft 93, i.e., the center of the substrate support surface 91a.

The fluid is continuously supplied into the recesses 91 b from the fluidsource 96 through the fluid supply passages 92. The fluid overflows therecesses 91 b to flow through a gap (space) between the lower surface ofthe wafer W and the substrate support surface 91 a of the support stage91. The gap is filled with the fluid, so that the wafer W is supportedby the fluid pressure. The wafer W and the support stage 91 are kept outof contact with each other with a clearance in a range of 50 μm to 500μm. Since the hydrostatic support mechanism 90 supports the wafer W viathe fluid pressure without contacting the wafer W, any damage to microdevices formed on the lower surface of the wafer W can be prevented. Thefluid used in the hydrostatic support mechanism 90 may be a liquid, suchas pure water. While the support stage 91 illustrated in FIG. 22 hasthree recesses 91 b, the present invention is not limited to thisembodiment. For example, the support stage 91 may have one recess ormore than three recesses. The support stage 91 may have three to sixrecesses.

It is also possible to use as the fluid a gas (e.g., air or nitrogen)which is a compressible fluid, rather than the liquid which is anincompressible fluid. When the compressible fluid is used, the recesses91 b may be omitted. In this case, the fluid supply passages 92 haveopen ends thereof lying in flat substrate support surface 91 a. The gasis supplied through the fluid supply passages 92 to the gap between thesubstrate support surface 91 a and the wafer W to support the wafer Wvia the pressure of the gas such that the wafer W is kept out of contactwith the substrate support surface 91 a. The fluid supply passages 92may have a number of open ends arranged over the substrate supportsurface 91 a in its entirety.

The scrubbing surface of the scrubber 50 and the substrate supportsurface 91 a of the hydrostatic support mechanism 90 are arrangedsymmetrically about the wafer W. Specifically, the scrubbing surface ofthe scrubber 50 and the substrate support surface 91 a of thehydrostatic support mechanism 90 are arranged such that the wafer W isinterposed therebetween. The load applied from the scrubber 50 to thewafer W is supported from right below the scrubber 50, i.e., from theopposite side of the scrubber 50, by the hydrostatic support mechanism90. Therefore, the scrubber 50 can exert a large load on the uppersurface of the wafer W. As shown in FIG. 4, the scrubbing surface andthe substrate support surface 91 a are arranged concentrically to eachother. The scrubber 50 may be arranged such that an edge portion of thescrubbing surface is located on the center of the wafer W. The diameterof the scrubbing surface may be equal to or slightly smaller than theradius of the wafer W. The diameter of the scrubbing surface and thediameter of the substrate support surface 91 a are approximately thesame. In this embodiment, the diameter of the substrate support surface91 a is slightly smaller than the diameter of the scrubbing surface,whereas the diameter of the substrate support surface 91 a may be equalto or larger than the diameter of the scrubbing surface.

Next, operations of the substrate processing apparatus according to theabove-described embodiment will be described below. The scrubber 50 ismoved to the retreat position outside of the substrate rotatingmechanism 10. In this state, the wafer W is transported to a positionabove the substrate rotating mechanism 10 by a non-illustrated transferdevice. The lift mechanism 30 elevates the chucks 11 and the wafer W isplaced on the upper ends of the chucks 11. When the chucks 11 arelowered, the wafer W is held by the clamps 40 of the chucks 11. Thewafer W is held such that the surface with no device faces upward andthe surface with devices formed thereon faces downward. Depending on thepurpose of substrate processing, the wafer W may be held by thesubstrate rotating mechanism 10 such that the surface with devicesformed thereon faces upward and the surface with no device facesdownward.

The scrubber 50 is moved from the retreat position to the processingposition. The wafer W is rotated at a predetermined speed by thesubstrate rotating mechanism 10. A rotational speed of the wafer W whenthe scrubber 50 is performing substrate processing may be in the rangeof 300 to 600 rotations per min. The support stage 91 is elevated by thestage elevating device 98 until the substrate support surface 91 a islocated close to the lower surface of the wafer W. Then, the fluid,which may be pure water, is continuously supplied into the recesses 91 bto support the wafer W via the fluid pressure. While supporting thewafer W, the support stage 91 is rotated by the stage rotating mechanism99. A rotational speed of the support stage 91 may be in the range of 20to 100 rotations per min.

The scrubber 50 is rotated by the scrubber rotating mechanism 58, andlowered by the scrubber elevating mechanism 52 until the cleaning tapes61 are brought into contact with the upper surface of the wafer W. Theupper surface of the wafer W is processed by the scrubbing surfaceformed by the cleaning tapes 61 that rotate about the central axis ofthe scrubber 50, while the pure water as the processing liquid issupplied onto the upper surface of the wafer W from the cleaning liquidsupply nozzle 27. The processing liquid may be a polishing liquidcontaining abrasive grains, instead of the pure water. The cleaningtapes 61 may be cleaning tapes having abrasive grains fixed to theirsurfaces. Without using the processing liquid, the cleaning tapes 61 ina dry state may be placed in sliding contact with the wafer W.

During the scrubbing process, the wafer W is supported from below by thehydrostatic support mechanism 90. In this state, the scrubber 50 bringsthe cleaning tapes 61 into sliding contact with the upper surface of thewafer W while rotating the cleaning tapes 61 about the central axis ofthe scrubber 50 to thereby remove the foreign substances deposited onthe upper surface of the wafer W and the scratches on the upper surfaceof the wafer W. Since the wafer W is supported by the hydrostaticsupport mechanism 90, the scrubber 50 can bring the cleaning tapes 61into sliding contact with the upper surface of the wafer W at a largeload. Accordingly, the scrubber 50 can remove relatively large foreignsubstances and foreign substances firmly stuck into the surface of thewafer W which could not be removed by a conventional cleaning apparatus.

The scrubber 50 and the wafer W are rotated in the same direction. Therotational speed of the scrubber 50 is selected such that relative speedbetween the wafer W and the cleaning tapes 61 is the same in allportions of the cleaning tapes 61 contacting the wafer W. The rotationalspeed of the scrubber 50 is determined depending on the rotational speedof the wafer W. Specifically, a ratio of the rotational speed of thescrubber 50 to the rotational speed of the wafer W is such that therelative speed between the wafer W and the cleaning tapes 61 is the samein all wafer portions of the cleaning tapes 61. For example, when therotational speed of the wafer W is 500 rotations per min and therotational speed of the scrubber 50 is 150 rotations per min, therelative speed between the wafer W and the cleaning tapes 61 becomesuniform. Such a speed ratio can be determined by known calculation orsimulation. By rotating the scrubber 50 and the wafer W at such arotational speed ratio, the upper surface of the wafer W in its entiretycan be processed uniformly. Therefore, the substrate processingapparatus according to the present embodiment can process the surface ofthe wafer W in its entirety from the center to the peripheral edgethereof more uniformly than a conventional pen-sponge cleaning machinein which a pen brush is rotated about its own axis and a conventionalroll sponge cleaning machine in which a roll sponge is rotated about itsown axis.

After the scrubbing process is finished, the scrubber 50 is moved to theretreat position, and the supply of the fluid to the support stage 91 isstopped. The support stage 91 is then lowered by the stage elevatingdevice 98 to a predetermined position. This predetermined loweredposition may be located away from the lower surface of the wafer W by adistance in the range of 30 mm to 50 mm. In this lowered position, thesupport stage 91 is rotated at a low speed (e.g., in the range of 10 to50 rotations per min), while the substrate support surface 91 a of thesupport stage 91 is supplied with a rinsing liquid, e.g., pure water,from a rinsing liquid supply nozzle (not shown). In this manner, thesubstrate support surface 91 a is rinsed with the rinsing liquid in thelowered position.

After the support stage 91 is lowered, the pure water as the cleaningliquid is supplied to the upper surface of the wafer W from the cleaningliquid supply nozzle 27 while the wafer W is rotated to wash away thedebris produced in the scrubbing process. Thereafter, if necessary, afluid mixture of a liquid and a compressed gas may be supplied to theupper surface of the wafer W from a two-fluid jet nozzle 100 so as toremove fine foreign substances and debris which could not be removed bythe scrubber 50. The two-fluid jet nozzle 100 is disposed above thewafer W. During cleaning of the wafer W, the wafer W may be supported bythe hydrostatic support mechanism 90.

FIG. 23 is a plan view illustrating the motions of the two-fluid jetnozzle 100. As shown in FIG. 23, the two-fluid jet nozzle 100 is mountedto a distal end of a rotary arm 101 whose proximal end is rotatablycoupled to a swing arm 102. The swing arm 102 houses therein a rotatingmechanism (not shown) for rotating the rotary arm 101 in a horizontalplane. Therefore, together with the rotatable arm 101, the two-fluid jetnozzle 100 is rotated above the wafer W by the rotating mechanism. Theliquid and the gas are supplied to the two-fluid jet nozzle 100, whichsupplies a jet of the fluid mixture of the liquid and the gas onto theupper surface of the wafer W. The two-fluid jet nozzle 100 rotates alonga circular path, indicated by a dot-and-dash line, which has a diameterslightly larger than the radius of the wafer W. Therefore, the uppersurface of the wafer W in its entirety can be cleaned by the jet of thefluid mixture.

In this embodiment, the cleaning liquid supply nozzle 27 and thetwo-fluid jet nozzle 100 constitute a cleaner for cleaning the wafer W.As shown in FIG. 4, the cleaning liquid supply nozzle 27 and thetwo-fluid jet nozzle 100 are disposed in the processing chamber 7. Thecleaning liquid supply nozzle 27 also functions as a processing liquidsupply nozzle for supplying the processing liquid to the wafer W whenthe wafer W is scrubbed. In another embodiment, a processing liquidsupply nozzle may be provided separately from the cleaning liquid supplynozzle 27, as shown in FIGS. 3A and 3B.

The wafer W that has been cleaned is then rotated at a high speed by thesubstrate rotating mechanism 10, so that the wafer W is spin-dried. Inthis spin-dry process, the wafer W is rotated at a speed in the range of1500 to 3000 rotations per min. Since no rotating element exists belowthe wafer W when being dried on the hollow substrate rotating mechanism10, watermarks due to droplets and attachment of the foreign substancescan be prevented. After the wafer W is dried, the chucks 11 are elevatedby the lift mechanism 30, releasing the wafer W therefrom. The wafer Wis removed from the substrate processing apparatus by the transferdevice (not shown). In this manner, the substrate processing apparatusaccording to the embodiment is capable of successively scrubbing,cleaning or rinsing, and drying the wafer W while holding the wafer W bythe substrate rotating mechanism 10. Therefore, attachment of theforeign substances to the wafer W when transported and diffusion ofcontaminations from the wet wafer W to a transfer path can be prevented.Moreover, a process tact time can be reduced.

As described above, the substrate rotating mechanism 10 functions as adrier for drying the cleaned wafer W. The substrate processing apparatusmay additionally have, as the drier, a mechanism for drying the wafer Wby supplying a low-vapor-pressure solvent to the wafer W. FIG. 24 is aside view showing an example of the substrate processing apparatushaving a drying liquid supply nozzle 110 for supplying thelow-vapor-pressure solvent onto the upper surface of the wafer W. Asshown in FIG. 24, the drying liquid supply nozzle 110 is disposed abovethe wafer W held by the substrate rotating mechanism 10. This dryingliquid supply nozzle 110, which is located in the processing chamber 7,is movable in the radial direction of the wafer W. While moving in theradial direction of the wafer W, the drying liquid supply nozzle 110supplies the low-vapor-pressure solvent to the upper surface of thewafer W. The cleaning liquid on the wafer W is replaced with thelow-vapor-pressure solvent, which is then evaporated to dryness, wherebythe wafer W is dried. The low-vapor-pressure solvent may be isopropylalcohol, for example.

FIG. 25 is a side view showing another example of the substrateprocessing apparatus having a drying gas supply nozzle 111 instead ofthe drying liquid supply nozzle. As shown in FIG. 25, the drying gassupply nozzle 111 is disposed above the wafer W held by the substraterotating mechanism 10. The drying gas supply nozzle 111 is movable inthe radial direction of the wafer W. While moving in the radialdirection of the wafer W, the drying gas supply nozzle 111 supplies adrying gas to the upper surface of the wafer W to thereby dry the waferW. The drying gas may be highly pure nitrogen, clean air, or the like.

Structural details of the substrate rotating mechanism 10 will bedescribed below. FIG. 26A is a plan view showing the clamp 40 of thechuck 11, and FIG. 26B is a side view of the clamp 40. As shown in FIGS.26A and 26B, the clamp 40 is formed at the upper end of the chuck 11.This clamp 40 has a circular or cylindrical horizontal cross section andis arranged so as to contact the peripheral edge of the wafer W tothereby hold the wafer W. The chuck 11 has a positioning portion 41extending from the clamp 40 to the central axis of the chuck 11. One endof the positioning portion 41 is connected integrally to a side surfaceof the clamp 40 and the other end is located on the central axis of thechuck 11. This center-side end of the positioning portion 41 has acurved side surface 41 a extending along a circle which is concentricwith the chuck 11. The upper end of the chuck 11 has a tapered surfaceinclined downwardly along the radially outward direction.

FIG. 27A is a plan view of the clamp 40 when holding the wafer W, andFIG. 27B is a plan view of the clamp 40 when releasing the wafer W. Thewafer W is placed on the upper end (the tapered surface) of each chuck11. When the chuck 11 is rotated in one direction, the clamp 40 isbrought into contact with the peripheral edge of the wafer W to therebyhold the wafer W, as shown in FIG. 27A. When the chuck 11 is rotated inthe opposite direction, the clamp 40 is separated from the wafer W tothereby release the wafer W, as shown in FIG. 27B. At this time, theperipheral edge of the wafer W is placed in contact with the curved sidesurface 41 a of the center-side end of the positioning portion 41. Thiscurved side surface 41 a of the positioning portion 41 can restrict adisplacement of the wafer W which occurs when the chuck 11 rotates. As aresult, subsequent wafer transferring operations can be performedstably.

FIG. 28A is a cross-sectional view taken along line A-A in FIG. 6, andFIG. 28B is a cross-sectional view taken along line B-B in FIG. 28A. Theannular flange 16 a of the rotary base 16 has a plurality of verticalthrough-holes in which the chucks 11 are inserted, respectively. Eachthrough-hole has a diameter slightly larger than the diameter of thechuck 11. Therefore, the chuck 11 inserted in the through-hole isvertically movable relative to the rotary base 16 and is rotatable aboutits central axis.

The spring stopper 11 a is secured to the lower end of each chuck 11.The spring 18, disposed around the chuck 11, is supported by the springstopper 11 a. An upper end of the spring 18 presses the flange 16 a ofthe rotary base 16 upwardly. Therefore, the spring 18 exerts a downwardforce on the chuck 11. The chuck 11 has a chuck stopper 11 b on thecircumferential surface thereof above the rotary base 16. This chuckstopper 11 b has a diameter larger than the diameter of the through-holein the flange 16 a. Therefore, a downward movement of the chuck 11 islimited by the chuck stopper 11 b, as shown in FIG. 28A.

A first magnet 43 is embedded in the rotary base 16 so as to face a sidesurface of the chuck 11. A second magnet 44 and a third magnet 45 areprovided in the chuck 11. The second magnet 44 and the third magnet 45are arranged away from each other in the vertical direction. The first,second, and third magnets 43, 44, and 45 may be neodymium magnets.

FIG. 29 is a schematic view showing the arrangement of the second magnet44 and the third magnet 45, as viewed from the axial direction of thechuck 11. As shown in FIG. 29, the second magnet 44 and the third magnet45 are arranged in different positions with respect to thecircumferential direction of the chuck 11. Specifically, a lineinterconnecting the center of the second magnet 44 and the center of thechuck 11 and a line interconnecting the center of the third magnet 45and the center of the chuck 11 intersect at a predetermined angle a asviewed from the axial direction of the chuck 11.

When the chuck 11 is in the lowered position shown in FIG. 28A, thefirst magnet 43 and the second magnet 44 face each other. As a result,an attractive force acts between the first magnet 43 and the secondmagnet 44. This attractive force generates a force of rotating the chuck11 about its central axis in a direction such that the clamp 40 pressesthe peripheral edge of the wafer W. Accordingly, the lowered positionshown in FIG. 28B is a clamp position at which the wafer W is held(clamped).

FIG. 30A is a cross-sectional view taken along the line A-A in FIG. 6when the chuck 11 is elevated by the lift mechanism 30, and FIG. 30B isa cross-sectional view taken along line C-C in FIG. 30A. When the chuck11 is elevated by the lift mechanism 30 to the elevated position shownin FIG. 30A, the first magnet 43 and the third magnet 45 face eachother, while the second magnet 44 is moved away from the first magnet43. As a result, an attractive force acts between the first magnet 43and the third magnet 45. This attractive force generates a force ofrotating the chuck 11 about its central axis in a direction such thatthe clamp 40 moves away from the wafer W. Accordingly, the elevatedposition shown in FIG. 30A is an unclamp position at which the wafer Wis released (unclamped).

Because the second magnet 44 and the third magnet 45 are arranged indifferent positions with respect to the circumferential direction of thechuck 11, the rotating force acts on the chuck 11 as the chuck 11 movesup and down. This rotating force imparts a force of holding the wafer Wand a force of releasing the wafer W to the clamp 40. Therefore, by justmoving the chuck 11 vertically, the clamp 40 can hold and release thewafer W. In this manner, the first magnet 43, the second magnet 44, andthe third magnet 45 function as a holding mechanism (clamp mechanism)for holding the wafer W by rotating the chuck 11 about its central axisto cause the clamp 40 to hold the wafer W. This holding mechanism isactuated by the vertical movement of the chuck 11.

The chuck 11 has an axially extending groove 46 formed on a side surfacethereof. The groove 46 has a circular arc horizontal cross-sectionalshape. The flange 16 a of the rotary base 16 has a protrusion 47projecting into the groove 46. This protrusion 47 has its tip endlocated within the groove 46 and loosely engaging the groove 46. Thegroove 46 and the protrusion 47 serve to limit the rotation angle of thechuck 11.

FIG. 31 is a cross-sectional view showing another example of thesubstrate rotating mechanism 10. In this example, magnetic bearings 21and 22 are used instead of the angular contact ball bearings 20 shown inFIG. 5. The rotary base 16 is rotatably supported by the magneticbearing 21 which is a radial magnetic bearing and the magnetic bearing22 which is an axial magnetic bearing. A touchdown bearing 30 isdisposed above the radial magnetic bearing 21 and another touchdownbearing 30 is disposed below the axial magnetic bearing 22. Since therotary base 16 is kept out of contact by the magnetic bearings 21 and22, no particles are produced when the wafer W is in rotation and hencethe wafer W is maintained in a clean atmosphere.

FIG. 32 is a cross-sectional view showing still another example of thesubstrate rotating mechanism 10. In this example, non-contact gasbearings 35 and 36 are used instead of the angular contact ball bearings20 shown in FIG. 5. The rotary base 16 is rotatably supported by the gasbearing 35 which is a radial gas bearing and the gas bearing 36 which isan axial gas bearing. A touchdown bearing 39 is disposed above theradial gas bearing 35 and another touchdown bearing 39 is disposed belowthe axial gas bearing 36. Since the rotary base 16 is kept out ofcontact by the gas bearings 35 and 36, no particles are produced whenthe wafer W is in rotation and hence the wafer W is maintained in aclean atmosphere. The gas bearings 35 and 36 may be hydrostatic gasbearings or dynamic pressure gas bearings. The stationary member 14 hasan exhaust port (not shown) defined therein. A gas from the gas bearings35 and 36 is discharged through the exhaust port. Therefore, heatgenerated by the hollow motor 12 can be released out of the substraterotating mechanism 10 together with the gas, so that distortion of therotary base 16 and other components due to heat can be prevented. As aresult, rotational accuracy of the substrate rotating mechanism 10 canbe increased. The substrate rotating mechanism 10 can therefore rotatethe wafer W at a higher speed to thereby dry the wafer W in a shortenedperiod of time.

FIG. 33 is a side view of another example of the scrubber 50. Thescrubber 50 in this example is coupled to the swing arm 53 through achuck mechanism (or coupling) 72, which is provided on the scrubbershaft 51. This chuck mechanism 72 is configured such that the scrubbershaft 51 can be separated from the swing arm 53 through the chuckmechanism 72. Therefore, the scrubber 50 can be detached in its entiretyfrom the swing arm 53 for replacement of the tape cartridges 60. Thescrubber 50 is detached when the scrubber 50 is in the retreat position,as shown in FIG. 34.

In the embodiments described thus far, the scrubber 50 is disposed atthe upper side of the wafer W, while the hydrostatic support mechanism90 is disposed at the lower side of the wafer W. In another embodiment,the scrubber 50 may be disposed at the lower side of the wafer W, whilethe hydrostatic support mechanism 90 may be disposed at the upper sideof the wafer W. According to this alternative embodiment, a throughputcan be increased because the wafer does not need to be inverted. Instill another embodiment, two scrubbers 50 may be disposed at the upperside and the lower side of the wafer W so as to process both surfaces ofthe wafer W simultaneously. In this embodiment using the two scrubbers50, the hydrostatic support mechanism 90 is not provided. The substraterotating mechanism 10 may include a plurality of roll chucks whichrotate about their central axes while holding the peripheral edge of thewafer. With the roll chucks used, the wafer cannot be spin-dried. Hencea separate drier is needed to dry the wafer.

FIG. 35 is a plan view of a substrate processing system including aplurality of substrate processing apparatuses described above. As shownin FIG. 35, the substrate processing system has a loading and unloadingsection 120 including four front loaders 121 on which wafer cassettes,each storing a number of wafers therein, are placed. Each of the frontloaders 121 is capable of receiving thereon an open cassette, an SMIF(Standard Manufacturing Interface) pod, or a FOUP (Front Opening UnifiedPod). The SMIF and FOUP are a hermetically sealed container which housesa wafer cassette therein and covers it with a partition wall to therebyprovide interior environments isolated from an external space.

The loading and unloading section 120 further includes a first transferrobot (loader) 123 movable along the array of the front loaders 121. Thefirst transfer robot 123 can selectively access the wafer cassettesinstalled on the front loaders 121 and can remove the wafer from thewafer cassettes. A particle counter 124 is disposed adjacent to thefirst transfer robot 123. This particle counter 124 is a device forcounting the number of foreign substances, i.e., particles, attached tothe wafer surface. The particle counter 124 may be omitted.

The substrate processing system further includes: a second transferrobot 126 movable horizontally, a plurality of substrate processingapparatuses 127 arranged along a moving direction of the second transferrobot 126, a first wafer station 131 and a second wafer station 132through which the wafer is transported between the first transfer robot123 and the second transfer robot 126, and an operation controller 133for controlling overall operations of the substrate processing system.In this example, the substrate processing system has four substrateprocessing apparatuses 127, which are arranged such that two substrateprocessing apparatuses 127 are installed on each side of the secondtransfer robot 126. The substrate processing system may include six oreight or more substrate processing apparatuses 127. When six substrateprocessing apparatuses 127 are provided, three substrate processingapparatuses 127 are disposed on each side of the second transfer robot126. When eight substrate processing apparatuses 127 are provided, foursubstrate processing apparatuses 127 are disposed on each side of thesecond transfer robot 126.

The operations of the substrate processing system are as follows. Thewafer is removed from the wafer cassette on one of the front loaders 121by the first transfer robot 123 and carried to the particle counter 124.The particle counter 124 counts the number of particles (foreignsubstances) attached to the wafer surface, and sends the counted numberto the operation controller 133. The operation controller 133 may changeprocessing recipes at the substrate processing apparatus 127 dependingon the counted number of particles. For example, if the counted numberof particles is greater than a predetermined reference value, then thesubstrate processing apparatus 127 may increase a time of the scrubbingprocess.

The wafer is removed from the particle counter 124 by the first transferrobot 123 and then placed on the first wafer station 131. The secondtransfer robot 126 holds the wafer on the first wafer station 131, andtransfers the wafer into either one of the four substrate processingapparatuses 127.

The substrate processing apparatus 127 processes the front-side surfaceor the backside surface of the wafer according to the operation sequencedescribed above. If necessary, a secondary process may be performed onthe processed wafer in another substrate processing apparatus 127. Theprocessed wafer is carried from the substrate processing apparatus 127to the second wafer station 132 by the second transfer robot 126. Thewafer is further carried from the second wafer station 132 by the firsttransfer robot 123 to the wafer cassette and is returned to an originalposition where the wafer has been stored.

The substrate processing system can selectively perform a serial processin which the wafer is processed successively by the plurality ofsubstrate processing apparatuses 127, a parallel process in which aplurality of wafers are processed in parallel by respective substrateprocessing apparatuses 127, and a serial-and-parallel process in which aplurality of wafers are processed by the plurality of substrateprocessing apparatuses 127 in serial and in parallel.

FIG. 36 is a plan view showing another example of the substrateprocessing system. The substrate processing system shown in FIG. 36 isessentially the same as the substrate processing system shown in FIG. 35except that the second wafer station 132 has an inverting mechanism 134for inverting the wafer. The wafer is carried from the wafer cassette tothe second wafer station 132 by the first transfer robot 123, andinverted by the inverting mechanism 134 of the second wafer station 132.The inverted wafer is carried by the second transfer robot 126 to one ofthe substrate processing apparatuses 127, where the wafer is processed.The processed wafer is carried to the second wafer station 132 again andinverted by the inverting mechanism 134. Thereafter, the wafer isreturned to the wafer cassette by the first transfer robot 123.

In the substrate processing systems shown in FIGS. 35 and 36, thesubstrate processing apparatuses 127 are arranged in the same plane.Alternatively, the substrate processing apparatuses may be arrayed alongthe vertical direction. FIG. 37 is a side view of the substrateprocessing system having the substrate processing apparatuses arrayed inan upper tier and a lower tier. The substrate processing system shown inFIG. 37 includes a first upper substrate processing apparatus 127A, afirst lower substrate processing apparatus 127B, a second uppersubstrate processing apparatus 127C, and a second lower substrateprocessing apparatus 127D. The first upper substrate processingapparatus 127A is disposed above the first lower substrate processingapparatus 127B, and the second upper substrate processing apparatus 127Cis disposed above the second lower substrate processing apparatus 127D.The second transfer robot 126 shown in FIG. 37 is movable not onlyhorizontally, but also vertically so as to carry the wafer between thefirst substrate processing apparatuses 127A and 127B, the secondsubstrate processing apparatuses 127C and 127D, and the second waferstation 132.

The substrate processing system shown in FIG. 37 is capable of providingvarious wafer processing lines. For example, as shown in FIG. 38, one oftwo wafers is transmitted to the upper substrate processing apparatuses127A and 127C as a first processing line, and the other is transmittedto the lower substrate processing apparatuses 127B and 127D as a secondprocessing line, so that the two wafers can be processed simultaneously.Alternatively, as shown in FIG. 39, four wafers may be transmitted tothe respective four substrate processing apparatuses 127A, 127B, 127C,and 127D as first to fourth processing lines. While FIGS. 37 through 39show the examples in which the substrate processing apparatuses arearranged in the two tiers, the substrate processing apparatuses may bearranged in three or more tiers.

The previous description of embodiments is provided to enable a personskilled in the art to make and use the present invention. Moreover,various modifications to these embodiments will be readily apparent tothose skilled in the art, and the generic principles and specificexamples defined herein may be applied to other embodiments. Therefore,the present invention is not intended to be limited to the embodimentsdescribed herein but is to be accorded the widest scope as defined bylimitation of the claims and equivalents.

What is claimed is:
 1. A substrate processing method for processing asubstrate having a first surface and a second surface, the secondsurface being an opposite side of the first surface, comprising:performing surface processing of the substrate by bringing a scrubbingmember into sliding contact with the first surface of the substratewhile supporting the second surface of the substrate by fluid pressurein a non-contact manner; cleaning the substrate that has been subjectedto the surface processing; and drying the cleaned substrate.
 2. Thesubstrate processing method according to claim 1, wherein the surfaceprocessing, the cleaning, and the drying are performed in a commonprocessing chamber.
 3. The substrate processing method according toclaim 1, wherein cleaning the substrate comprises: supporting the secondsurface of the substrate by the fluid pressure in a non-contact manner.4. The substrate processing method according to claim 1, wherein thefirst surface is a surface with no devices formed thereon, and thesecond surface is a surface with a device formed thereon.
 5. Thesubstrate processing method according to claim 1, wherein the firstsurface is a surface with devices formed thereon, and the second surfaceis a surface with no devices formed thereon.
 6. The substrate processingmethod according to claim 1, wherein a material forming the firstsurface comprises silicon, a silicon compound, gallium, a galliumcompound, metal, a metal compound, or an organic compound.
 7. Thesubstrate processing method according to claim 1, wherein the scrubbingmember comprises a material softer than a material forming the firstsurface, a material containing abrasive grains, or a polishing tape. 8.The substrate processing method according to claim 1, wherein performingsurface processing comprises: bringing the scrubbing member into slidingcontact with the first surface while supplying a processing liquid ontothe first surface, the processing liquid containing at least one of acomponent capable of dissolving a material forming the first surface,abrasive grains, or a component for preventing reattachment of thematerial removed by the scrubbing member or reaction products.
 9. Thesubstrate processing method according to claim 8, wherein the abrasivegrains comprise silicon dioxide, silicon carbide, silicon nitride,aluminum oxide, diamond, or a mixture of selected ones of thesematerials.
 10. The substrate processing method according to claim 8,wherein the processing liquid is neutral or alkaline.
 11. The substrateprocessing method according to claim 8, wherein the processing liquid isacidic.
 12. The substrate processing method according to claim 1,wherein: cleaning the substrate comprises supplying a cleaning liquidonto the first surface of the substrate and cleaning the first surfacewith a contact type or non-contact type cleaning technique; and thecleaning liquid comprises a solution having a predetermined pH, asolution containing a component for preventing reattachment of amaterial once removed by the scrubbing member, or pure water.
 13. Thesubstrate processing method according to claim 12, wherein the cleaningliquid is neutral or alkaline.
 14. The substrate processing methodaccording to claim 12, wherein the cleaning liquid is acidic.
 15. Thesubstrate processing method according to claim 1, wherein drying thecleaned substrate comprises: rotating the substrate at a high speed,supplying a gas to the first surface, or supplying a low-vapor-pressuresolvent to the first surface.
 16. The substrate processing methodaccording to claim 1, wherein drying the cleaned substrate comprises:holding the substrate by chucks which contact a peripheral edge of thesubstrate.
 17. The substrate processing method according to claim 1,wherein performing surface processing comprises: performing surfaceprocessing until the first surface has a surface roughness of 5 μm orsmaller.